Electrode support



July 4, 1939. N s n- 2,164,547

ELECTRODE SUPPORT Filed April 50, 1938 INVENTOR. NEWELL R. SMITH A TTORNEY- Patented July 4, 1939 ELECTRODE SUPPORT Newell R. Smith, Bloomfield, N. J., assignor, by mesne assignments, to Radio Corporation of America, New York, N. Y., a corporation of Delaware Application April 30, 1938, Serial No. 205,206

6 Claims. (01. 250----2'7.5)v

My invention relates to electron discharge deends of the side rods, and an openin o the vices, particularly to means for supporting tupp d of the thod S eeve s 80 Cut Out as bular electrodes such as indirectly heated cathto leave a short tongue or lug 3 extending a y ode sleeves for such devices. into the hole from one side. The insulating The usual electrode mount for a radio tube p r is w red ov r the end f h s v p 6 with insulating spacers engaging in holes the mitting the end of the sleeve to slide through its ends of a cathode sleeve and electrode side rods p n W h h n u 8 r vell ne groove is difiicult to assemble so as to prevent lateral 5 into notch That portion O t ve mas Well as lengthwise movement of the electrodes. prising the Wall Of the grOOVe is then straight- An exteriorly activated cathode sleeve containened out so that the bottom portion of the groove 10 ing an insulated heater is particularly difiicult to W overlies tongue 3 and locks e s ee d firmly secure in the spacers. The usual raised spac tegetherp assembly. the edge f t e dimples or embossings on the ends of the sleeve Op extends inwardly P the uter su ace to engage the insulator at the periphery of the of the sleeve. While the one end of the cathode hole through which the sleeve is inserted does is p t e y leeked nst movement in either 5 not positively lock the sleeve to prevent lengthan up d a w w d d rection the other wise movement. Metal tabs sometimes used for e d 0f t sleeve is preferably e to s de 10nsecuring the sleeve in place distort the sleeve gitlldihally in its spacerand are difiicult to attach. Cathode sleeves se- While the particular electrode ted for ilcured at each end are not free to longitudinal lustrstihg y invention is a Cathode sleeve. it 20 expansion and usually bow or buckle at the is Obvious that any tubular electrode y he center. mounted according to my invention where one An object of my invention is u o t means end of the electrode must be locked against for a tubular electrode for electron discharge demovement slid the Othel" end slidably ed 130 vices which may be positively locked against end- Permit thermal eXpahsiOIL 25 wise movement, which is free to expand without The embodiment 010 y inVentiDn s own in bowing or buckling and which is easy to make Figure 4 comprises a Cathode With e groove 6 and assemble in such devices. terminating in an indentation 9. The length of My invention is defined with particularity in the tongue 3 may be chosen so as to s ide with the appended claims and preferred embodiments some friction along groove 3 so that it Will p 30 are described in the following specification and into the indentation 9 d lock e Cathode and are shown in the attached drawing in which Figspacer to e ure 1 shows an electron discharge device with a e otc suc as the Window 1 or indentacathode embodying my invention, Figures 2 and 3 tion 9, may conveniently be formed or blanked are perspective and top views, respectively, of one Out in flat sheet metal, such as nickel, and t e 35 th d embodying my invention, and Figures 4 metal then rolled into tubular sleeves with recd 5 h th th d embodying t chartangular or round cross section and seamed as by acteristic features of my invention, welding to complete the sleeve. The round sleeve The tube shown in Figure 1 comprises an elecshown in Figure 5 s provided With a flattened trade assembly with insulating spacers I hi h or slightly indented groove or secant It terminat- 40 engage the end of the cathode 2 exteriorly acin in Window The spacer Opening s made tivated with the usual oxide coating and conto snugly fit the formed end of the sleeve so taining an insulated heating element, and also t a it y be locked in Place e the Wall engage the ends of the side rods of anode 3 and at Hi is pu ed ut Over e p grid 4. The assembly is mounted upon the stem In assembling an electrode mount with my im- 45 of envelope 5, which may be exhausted, sealed proved cathode the side rods of the several elecofi and based in the usual manner. trodes are inserted at their lower ends in the One end of the tubular cathode 2, embodying lower spacer with the aid of a jig, the cathode is my invention and shown in detail in Figures 2 lowered into place, and the upper spacer is and 3, is provided with a short longitudinal pressed over the upper ends of the cathode and 5 groove 6 terminating in a notch such as a Winthe side rods, bringing the tongue 8 into registry dow or cut-out portion 1, the height of the notch with the notch I or 9, and the wall of the sleeve being approximately equal to the insulating drawn out to overlie the spacer by inserting one spacer thickness. The insulating spacer is protong of a pair of tweezers into the end of the vided with the usual perforations to receive the sleeve and pressing. 5

A cathode constructed according to my invention is easy to assemble in a mount so that it cannot move out of place. My improved cathode is positively locked against lengthwise movement yet is free at one end to expand when heated and is easy to make and assemble in electron discharge devices.

I claim:

1. An electron discharge device comprising a cathode sleeve, an insulating spacer having an opening to receive the end of said sleeve, a notch in said sleeve spaced inwardly from the end of the sleeve with the opposed edges of said notch bearing against opposite sides of said spacer at said opening to prevent longitudinal movement of the sleeve through the opening.

2. An electron discharge device comprising a plate-like insulating spacer having an opening, a cathode sleeve extending through said opening, said spacer at the edge of the opening extending inwardly past the outer surface of said sleeve for holding the sleeve against movement through the opening.

3. An electron discharge device comprising an anode, a tubular cathode in cooperative relation with said anode, means for insulatingly spacing said anode and cathode comprising a sheet of insulating material engaging the end of said cathode and attached to said anode and having an opening to receive the end of said cathode, a notch in said cathode inwardly from said end of said cathode, and a tongue on said sheet in the side of said opening extending into said notch.

4. An electron discharge device comprising an envelope, a tubular electrode with a notch near one end in said envelope, means for supporting said one end of said electrode comprising a spacer with an opening, opposed edges of said notch bearing against opposite sides of said spacer at said opening to prevent longitudinal movement of the electrode through the opening, and means for preventing lateral displacement of the other end of said electrode.

5. An electron discharge device comprising an envelope, a plurality of electrodes in said envelope, one of said electrodes being tubular and with a notch spaced inwardly from the end of the electrode, means for insulatingly spacing the electrodes comprising a spacer having an opening to receive the end of said one electrode, the edge of the opening extending inwardly past the outer surface of said one electrode for holding the electrode against longitudinal movement through the opening, and means at the other end of said one electrode for slidably guiding said other end.

6. In an electron discharge device the method of assembling a plate-like insulating spacer having an opening and a tubular cathode sleeve with a notch spaced from one end and a groove communicating at one end with the end of said sleeve and at the other end with said notch, comprising inserting said end of the sleeve in said opening to bring a portion of the edge of the opening into registry with said notch, and draw ing the wall of said groove outwardly to overlie said spacer.

NEWELL R. SMITH. 

